Elasmobranchii (sharks and rays) > Rajiformes
(Skates and rays) > Arhynchobatidae
Etymology: Notoraja: Greek, noton = back + Latin, raja = fish, Raja sp. (Ref. 45335); hesperindica: Name from combination of Greek 'hesper' for westerly, and Latin 'indicus' for Indian, referring to the distribution of the new species..
Environment: milieu / climate zone / depth range / distribution range
Marine; bathydemersal; depth range 1230 - 1600 m (Ref. 123885). Deep-water
Western Indian Ocean: off southern Mozambique and off northwestern Madagascar.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 53.3 cm TL male/unsexed; (Ref. 123885)
Morphology | Morphometrics
This species is distinguished from most of its congeners by the intense dark blue-grayish coloration and large dorsolateral tail thorns. It is further distinct with the following characters: disc evenly inverse heart-shaped, with broadly rounded outer corners; body length to mid-cloaca is shorter than tail length from mid-cloaca; snout very long direct preorbital length 15.1-16.7% TL.; orbits are relatively small, horizontal diameter 0.9-1.2 times interorbital width; dorsal surface nearly completely devoid of denticles except the trunk area close to pectoral axils where bands of few denticles start and continue as more pronounced rows on tail; anterior tail with several short rows of spinules and a rather regular row of small spinules on lateral tail; one small preorbital thorn on each side; a regular or irregular row of about 16-25 small median tail thorns; lateral tail with 2 irregular rows of about 15-25 dorsolateral thorns that are much larger than the median thorns. Colouration when fresh, the dorsal disc plain intense dark blue, somewhat mottled blackish-brown in the orbital and snout regions, pelvic fins and claspers medium brownish blue, tail dark blackish blue; the ventral surface dark (Ref. 123885).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Weigmann, S., B. Séret and M.F.W. Stehmann, 2021. Notoraja hesperindica sp. nov., a new colorful deep-sea softnose skate (Elasmobranchii, Rajiformes, Arhynchobatidae) and first generic record from the western Indian Ocean. Mar. Biodiv. 51(2):online. (Ref. 123885)
IUCN Red List Status (Ref. 125652)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82804
= No PD50 data [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00575 (0.00290 - 0.01143), b=3.09 (2.92 - 3.26), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.8 ±0.7 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): Low, minimum population doubling time 4.5 - 14 years (Preliminary K or Fecundity.).
Fishing Vulnerability (Ref. 59153
): Moderate vulnerability (41 of 100).